It has long been recognized that a reserve activated electrochemical cell will have a significantly longer life prior to its use than does a cell which is activated during its manufacture. Many designs have been proposed for a single unitary package containing an electrochemical cell ready for operation, minus one or more of its components, which component is separated in another portion of the package. By one means or another, the missing component is brought into contact with the cell and activation occurs upon the activation of such a means.
By far the most common method for preparing a reserve activated cell is to separate the electrolyte from the anode and cathode. Thus, the rapidly movable electrolyte solvent, with or without the electrolyte salt, is maintained in an inert environment remote from the active materials of the cell until it is needed.
Many prior art methods exist for separating the electrolyte and the remaining parts of the battery until the desired time for bringing them together. These methods include the placement of a frangible barrier between the electrolyte and the cell, the use of a completely destructable capsule for either the electrolyte or the cell, and the like. However, all of these prior art methods are either too expensive or so intricate that their reliability is not sufficiently acceptable. Accordingly, it is an object of this invention to provide a reserve activated electrochemical cell.
Another object of this invention is to provide an inexpensive and reliable reserve activated cell which is capable of long shelf life prior to activation and yet which is capable of delivering a reasonable amount of energy during its active or useful life.
Other objects will appear hereinafter.